\section{Introduction}
\label{sec:intro}
In the coming years, nuclear fusion establishment as energy source will require
the use of teleoperated systems mainly due to the radiation. The nuclear
industry has used remote systems due to the environmental constraints since
the beginning, but with the technological advances there is a need for
implementing innovative systems. It is because of this novelty that important
works have to be carried out in order to obtain drive mechanisms, sensors,
viewing systems, electrical cables, connectors, electronics for signal
communications, etc., suitable for the below mentioned conditions.
  
Such teleoperated system should deal high radiation, ultra-high vacuum, high
temperature and the toroidal magnetic field with the intention of performing
inspection, maintenance and repair of the nuclear fusion facility such as the
International Thermonuclear Experimental Reactor (ITER), DEMO or the
International Fusion Materials Irradiation Facility (IFMIF).

This paper is focused on the challenges of teleoperation in a nuclear
environment . First, in section \ref{sec:state} the state of the art is
presented, covering some of the successful developments that overcome one or
more of the nuclear fusion constraints. At this point, it is important to
highlight that the authors do not have knowledge about a robotic system capable
to face all the constraints. Next in section \ref{sec:radiation} the components
and systems fitted to cope with the radiation constraint are discussed taking as
a reference point the radiation doses expected in the operation of ITER. Next,
the ultra-high vacuum (section \ref{sec:vacuum}) and high temperature (section
\ref{sec:temperature}) constraints are addressed with the review of some
materials and approaches that have been proved suitable for each or both of
these conditions. In section \ref{sec:magnetic} the magnetic field direct
effects are taken into consideration since, it appears from the state of the
art, there is not a system that fulfill such as hostile constraint.

Finally in section \ref{sec:conclusions} the conclusions from this work are
presented.